You can check whetehr it is installed or not in Control Panel > Add or Remove Programs(Windows XP) or Uninstall Program (Windows 7) and check whether above mentioned software are listed, if not please download and install it.

3. Please open services.msc, by opening Run window (you can open Run window, by pressing Windows key + R key on keyboard) and typing services.msc in the Run window and hit enter.

You will get a new Services window, please search for Windows Installer in the Services window, and check whether it is started, if not please double click on the Windows Installer and click on Start button.

Please do the same for Windows Modules Installer in the Services window.

4. Now, please try to install the product, if you are still getting the error, please continue the troubleshooting steps from the 5th step.

5. Open Command Prompt, by opening Run window and typing cmd and then hit enter.

a) In Command Prompt window, Type sfc /SCANNOW and press Enter.

b) When the system scan completes, type msiexec /unreg in the Command Prompt window, and press Enter.

Another trouble. After I installed Net Framework yesterday (4.0.30319) and do some of the things you´ve mencioned. After I restarted my PC I opened ones more my Windows Live Mail and with surprise it apeared that is necessary to install NET framework 4.0.30319.... O_O. I allready installed it. WTF.

I don't know, if it's still relevant. I had the same problem. After days or weeks trying I installed WindowsServer. At the same time I downgraded to an older sevicepack. Then I could install it. I thought it has been the WindowsServer. I didn't install it, when I was installing the Internet Explorer. so here you can download it. It's in the IE-package: